COIL DEVICE

• US 20170154720A1
• Filed: 11/29/2016
• Published: 06/01/2017
• Est. Priority Date: 11/30/2015
• Status: Active Grant

• Current Assignee: TDK Corporation
• Original Assignee: TDK Corporation
• Inventors: TONOYAMA, Kyohei, SATO, Shigeki, OHKUBO, Hitoshi
• Granted Patent: US 11,049,641 B2
• Time in Patent Office: Days
• CPC Class Codes: H01F 17/0013 with stacked layers
• CPC Class Codes: H01F 17/04 with magnetic core
• CPC Class Codes: H01F 2017/048 with encapsulating core, e.g. made of resin and magnetic powder
• CPC Class Codes: H01F 2027/2809 on stacked layers
• CPC Class Codes: H01F 27/022 Encapsulation
• CPC Class Codes: H01F 27/255 made from particles H01F27/26 takes precedence
• CPC Class Codes: H01F 27/2804 Printed windings
• CPC Class Codes: H01F 27/292 Surface mounted devices
• CPC Class Codes: H01F 27/324 Insulation between coil and core, between different winding sections, around the coil; Other insulation structures
• CPC Class Codes: H01F 27/42 Circuits specially adapted for the purpose of modifying, or compensating for, electric characteristics of transformers, reactors, or choke coils circuits for controlling transformers, reactors or choke coils, for the purpose of obtaining a desired output H02P13/00; impedance networks H03H

Abstract

A coil device comprising a coil, and a magnetic metal powder containing resin covering said coil. Said magnetic metal powder comprises at least two types of magnetic metal powders with different D50. The magnetic metal powder having larger D50 is defined as a large diameter powder, and the magnetic metal powder having smaller D50 is defined as a small diameter powder among the two types of said magnetic metal powder. Said large diameter powder is made of iron or iron based alloy. Said small diameter powder is made of Ni—Fe alloy. Said small diameter powder has D50 of 0.5 to 1.5 μm. Said large diameter powder and said small diameter powder respectively comprises an insulation coating layer.

Claims

1. A coil device comprising a coil, and a magnetic metal powder containing resin covering said coil, wherein

said magnetic metal powder comprises at least two types of magnetic metal powders with different D50,

the magnetic metal powder having larger D50 is defined as a large diameter powder, and the magnetic metal powder having smaller D50 is defined as a small diameter powder among the two types of said magnetic metal powder,

said large diameter powder is made of iron or iron based alloy,

said small diameter powder is made of Ni—

Fe alloy,

said small diameter powder has D50 of 0.5 to 1.5 μ

m, and

said large diameter powder and said small diameter powder respectively comprises an insulation coating layer.

2. The coil device as set forth in claim 1, wherein said large diameter powder has D50 of 15 to 40 μ

m.

3. The coil device as set forth in claim 1, wherein said small diameter powder has D50 of 0.5 to 1.0 μ

m (1.0 μ

m not included).

4. The coil device as set forth in claim 1, wherein said small diameter powder has D90 of 4.0 μ

m or less.

5. The coil device as set forth in claim 1, wherein at least said small diameter powder is spherical.

6. The coil device as set forth in claim 1, wherein a content ratio of Ni in said Ni—

Fe alloy is 75 to 82%.

7. The coil device as set forth in claim 1, wherein the blending ratio of said small diameter powder in entire said magnetic metal powder is 5 to 25%.

8. The coil device as set forth in claim 1, wherein a thickness of said insulation coating layer is 5 to 45 nm.

9. The coil device as set forth in claim 1, wherein said insulation coating layer includes a glass comprising SiO₂.

10. The coil device as set forth in claim 1, wherein said insulation coating layer includes phosphates.

11. The coil device as set forth in claim 1, further comprising an intermediate diameter powder wherein D50 of said intermediate diameter powder is smaller than that of said large diameter powder and larger than said small diameter powder.

12. The coil device as set forth in claim 11, wherein said intermediate diameter powder comprises an insulation coating layer.

13. The coil device as set forth in claim 11, wherein said intermediate diameter powder has D50 of 3.0 to 10 μ

m.

14. The coil device as set forth in claim 11, wherein said intermediate diameter powder is made of iron or iron based alloy.

15. The coil device as set forth in claim 11, wherein the blending ratio of said large diameter powder in said entire magnetic metal powder is 70 to 80%, and the blending ratio of said intermediate diameter powder is 10 to 15%, and the blending ratio of said small diameter powder is 10 to 15%.

16. A magnetic metal powder containing resin used for the coil device according to claim 1.

17. A magnetic metal powder used for the coil device according to claim 1.